HELP! How to get the frame number of webp format pictures in Browser.

[darklord]

How to get the frame number of webp format pictures in Browser.

[Yannis Guyon]

You should be able to get the frame count with the libwebp C API specified in demux.h:

WebPData webp_data;

webp_data.bytes = ...;  // Pointer to WebP file data

webp_data.size = ...;   // WebP file size

WebPDemuxer* demux = WebPDemux(&webp_data);

uint32_t frame_count = WebPDemuxGetI(demux, WEBP_FF_FRAME_COUNT);

...  // Use frame_count

WebPDemuxDelete(demux);

You may use the Emscripten JavaScript wrapper of libwebp to access it directly from a web page.

Alternatively you may use other implementations such as node-webpmux:

const WebP = require('node-webpmux');

let img = new WebP.Image();

await img.load('img.webp');

// Use img.frameCount

Please note that third party solutions are not endorsed by WebP-discuss.